Protective grease



Patented Aug. 21, 1945 UNITED STATES PATENT OFFICE PROTECTIVE GREASEJohn D. Morgan, South Orange, and Russell E. Lowe, East Orange, N. J.,assignors to Cities Service Oil Company, New York, N. Y., a corporationof Pennsylvania No Drawing. Application June 3, 1943,

Serial No. 489,444

'7 Claims. (Cl. 252-19) This invention relates to protective greases.More particularly the invention'relates to greases useful for protectingthe parts of ocean-going vessels, such as submarines, from corrosion andat the same time providing a, grease which when submerged in the waterwill not separate or give off a material which will make an oil film orslick on the surface of the water.

A moist atmosphere, water mists and ocean water are very corrosive tometal parts. Many parts may be protected by covering with paints tectingmechanical parts from corrosion and at the same time acting as alubricant when the parts are -moved.

Most of the lubricating greases now in iise have mineral oil lubricantsin them and when these greases are submerged in water they separate sothat the oil is released and comes to the surface of the water. Thisseparation is injurious to the grease, butmore important, however, isthe fact that the released oil (whether it is a mineral or vegetableoil) spreads a film or slick on the surface of the water and gives anindication of the location of the submerged submarine. Another object ofthe invention is to provide a greasewhich will not separate whensubmerged in the water and will not produce an oil slick.

The top or deck of the submarine has a large area or large number ofmechanical parts mounted on it. This surface and machinery must bethoroughly coated with grease to pro-' tect it. When the submarine. withits coated deck and machinery is submerged the movement of the submarineand the movement of the water act to wash off and remove grease from theparts. Although this grease may be insoluble, if it comes to the surfaceand floats on the surface of the water it will act as a telltale eventhough it is'not as easy to see the grease as it is to see an oil film.

Accordingly another object of the invention is to provide a protectivegrease which is waterinsoluble and which is heavier than the water sothat, if the grease becomes detached from the parts to which it'isapplied, it will sink in the water and not give any indication on thesurface of the water.

With these and other objects in view the invention consists in theprotective grease here inafter described and particularly defined in theclaims.

A grease which is water-insoluble and will not separate upon standingand which has a gravity heavier than water has the following formula:

Percent by weight Dark green petrolatum 68.64

Lithium stearate 8.80 Aluminum tristearate 1.76 Lead oleate (anhydrous)0.40 Triblityl phosphite 0.40 Leaf lead 20.00

This same type of grease, but which has a gravity less than the gravityof water so that it will float, has the following composition:

Percent by weight Dark green petrolatum 85.00 Lithium stearate 11.00Aluminum tristearate 2.20 Lead oleate (anhydrous) -s 0.50 Tributylphosphite 0.50

The grease having the leaf lead has a high' gravity and will sink inwater. Such a grease is very desirable for coating the mechanical 'partsH on the deck of a siibmarinc. On the other hand the grease describedabove which does not .have any leaf lead is a very desirable grease toplace on; the deck of other seagoing vessels which are not submergedbecause this grease is very adhesive; -It..,has good lubricatingqualities and is very efiective'in preventing corrosimi.

of the mechanical parts.

In order to make the greases described above,

the dark green petrolatum, which is a crude par-ts. The tributylphosphite is added as an antioxidant to maintain a uniform compositionof the grease so that the grease will not in itself act as a corrosiveagent for the mechanical parts.

' The leaf lead which is in the form of small, thin scalelike pieces oflead, acts as a weighting agent to increase the gravity of the greaseuAt the same time this finely divided lead gives extreme pressurecharacteristics to the grease and is a rust preventing agent. When thelead is-incorporated in the grease it does not separate and the leadwill carry the grease to the bottom of a body of water and hold itthere.

The greases have the following physical charaoteristics:

Grease containing leaf lead Percent by weight Dark green petrolatum68164 Lithium stearate 8.80 Aluminum tristearate 1.76 Lead oleate(anhydrous) 0.40 Tributyl phosphite 0.40 Leaf lead 20.00

6. A protective coating grease comprising:

Percent by weight Dark green petrolatum 85.80 Lithium -stearate 1100Aluminum tristearate -1 2.20 Anhydrous lead oleate 0.50 Tributylphosphite 0.50

Melting point -F 400 Oil separation when standing under water 0 Waterabsorbed at 70 F per cent 20 Penetration mm-.. 162.5 Corrosion to copper0 Specific gravity 1.048 Grease lighter than water Melting point ..F 400I Oil separation when standing under water 0 Water absorbed at 70 F; percent 20 Penetration mm 185.0 Corrosion to copper 0 Specific gravity0.868

The dark green petrolatum is a semi-refined petrolatumhaving a' meltingpoint of between 118 to 122 F. and a viscosity of 115 to 122 at 210 F.

The preferred form of the invention having been thus described what isclaimed as new is:

1. A protective grease for coating andprotecting the mechanicalequipment and other exposed metal parts on the outside of a submarine,comprising approximately 68% of crude petrolatum, approximately 8% of alithium soap, approximatelyv 2% of aluminum soap, a small proportion ofa lead soap, and approximately 20% of finely divided metallic lead.

\ 2. A protective grease for coating and protect; Y 8 the mechanicalequipment and Qtherexposed metal parts on the outside of a submarine,comsoap, the remainder of the composition being essentially crudepetrolatum.

4. A protective grease coating composition for coating exposedmechanical equipment and other metal parts, comprising approximately ofcrude petrolatum, approximately 11% of lithium stearate,- a, smallproportion of lead oleate, and

approximately 2% of aluminum stearate.

5. A submarine grease comprising:

7. The method of protecting the external ,rneehanical equipment andother metal parts of a submarine where such parts are exposed to theaction of sea water, which comprises applying to the metal parts to beexposed a protective coating comprising an intimately blended mixture ofapproximately 9% of lithium stearate, approximately 2% of aluminumstearate, a' small proportion of a lead soap, and approximately 20% offinely divided metallic lead, the remainder oi. the coating consistingessentially of crude petrolatum, said coating material having a specificgravity. greater than that of sea water whereby any of the coatingremoved from the submarine will sink and thereby avoid disclosing thelocation of the submarine.

JOHN D. MORGAN. RUSSELL E. LOWE.

